Poor Acceleration

Check Intake Manifold Pressure (IMP) sensor (Legacy and Outback).
Check Intake Air Temperature (IAT) sensor (Legacy and Outback).
Check intake air temperature and pressure sensor.
Check Mass Air Flow (MAF) sensor (Impreza WRX 2.0L).
Check Throttle Position (TP) sensor.
Check fuel injection components; fuel injectors, fuel pressure regulator and fuel filter.
Check fuel pump and fuel pump relay.
Check Engine Coolant Temperature (ECT) sensor, if symptom occurs only in cold temperatures.
Check Crankshaft Position (CKP) sensor, ensure component is securely installed.
Check Camshaft Position (CMP) sensor, ensure component is securely installed.
Check A/C switch and A/C cut relay.
Check engine torque control signal circuit.
Check ignition parts; ignitor, ignition coil and spark plugs.
Check EGR valve (Outback 3.0L).